The Catalytic Plug can be placed on the Ember Injector and will consume steam while the Injector is active. The Injector will also show "Catalytic Plug Speed: 4x" while viewing with an Ember Dial. However, the Injector is unaffected and will consume the same amount of ember and imbue a metal seed at the same speed as if there were no Plugs attached.

When testing this I did not notice the injectors not consuming the correct amount of ember but I can confirm that the seeds weren't growing any faster with a catalytic plug.

Thank you for bringing one of my favorite mods up to date. I appreciate your work.